Abstract
The synthesis of fatty acids was studied in enzyme systems obtained from pigeon liver tissue. Experimental evidence is presented to show that the formation of long-chain derivatives of coenzyme A occurs from acetaldehyde and malonyl coenzyme A in the presence of reduced triphosphopyridine nucleotide and Mn++ ions. Adenosine triphosphate is not required for the reaction. A mechanism for the synthesis of fatty acids is proposed on the basis of these findings.